Touring the Skies By: Jim Bonser (jbonser@usa.net)

June 27, 2014

Ps. 19:1 The heavens declare the glory of God; the skies proclaim the work of his hands. By the time you are likely to read this, Jupiter will be too close to the Sun to observe in the evening skies of July. If you have been watching its progress over the course of June you may have been surprised at how fast the biggest world in our solar system and has been moving toward the horizon night after night. Even though Jupiter does not line up with the Sun until July 24th, an event known as “superior conjunction” it will be lost in the glare of the Sun and haze near the Iowa horizon long before then. Astronomers use the word conjunction to mean that two objects line up in the sky. In the case of a solar system object such as a planet or asteroid there are two special terms to help describe the event. If the orbit of the planet is nearer to the Sun than ours, such as Venus or Mercury, then when the three of us line up (Sun - Venus - Earth, for example) then it is called an ‘inferior conjunction’ the planet passes between us and the Sun. When the other object orbits the Sun farther from the Sun than we do and the planet behind the Sun from our point of view (Jupiter - Sun - Earth, for example) then it is known as a ‘Superior conjunction’. After Jupiter passes superior conjunction on the 24th it will begin to rise before the Sun in the early morning skies. It has been fun watching Jupiter and reassuring to see its steady light dancing among the stars of Gemini this year. When it emerges from the glare of the Sun later this summer, rising a couple hours or so ahead of the Sun in August, it will have moved out of Gemini and into Cancer the Crab. Fortunately for those of us who prefer to do our observing after sunset instead of before sunrise, there are still two bright planets to enjoy this month: Mars and Saturn. Mars will move closer and closer to Spica as the month progresses. On July 1st, Mars will be about 5 degrees west of the bright star Spica. It will move a little each night toward the bright blue-white star until it overtakes it on the 14th when it will be very close, only a little over a degree apart. Mars will continue to move eastward compared to the background stars and by the end of the month, on July 31st, Mars will be over 9 degrees east of Spica. Wow! For a fun exercise, make a little drawing of the stars of Virgo, or even just Spica and then draw a dot representing Mars each time you go out and write the date next to it. If you do, I would love to see your drawings - you could scan them in to a computer and e-mail them to me! The other bright evening planet is spectacular Saturn. The color contrast between Mars and Saturn is striking. Mars is very reddish or orange in color while I always describe Saturn as being a golden yellow. Saturn is not very far away from Mars and comparing their colors will be easy this month. Saturn is to the east of Mars and Spica in the constellation Libra. Libra used to be part of the constellation Scorpius. I mention this because Saturn hovers just above the star called Zubenelgenubi, pronounced zoo-ben-ell-ga-noobi - almost like Obiwan Kenobi, Luke Skywalker’s Jedi mentor in Star Wars. Zubenelgenubi means ‘Southern Claw’ meaning it represented the southern claw of the Scorpion. A little ways above Saturn is Zebeneschamali or ‘Northern Claw’. I just love saying those names at star parties, they just roll off the tongue so nice! Although it is way too faint to view without a telescope, it is worth mentioning that Pluto will reach opposition this month on July 4th. It will therefore be as bright as it will get this year and really won’t change much all month. It takes a fairly large telescope to actually see faint Pluto - generally a scope with at least 6 inches of aperture or more. Pluto is in Sagittarius - which means there will be lots of stars in the field many of which will be brighter than our target. Sky and Telescope has a very good finder chart printed in its July issue as does Astronomy Magazine. I would encourage you to get a copy or check out the resources on their web sites to help you if you decide to try to see it for yourself. Finally, one last Solar System object of interest is comet C/2012 K1 Panstarrs. It is not quite visible without at least binoculars yet, but it might become bright enough to see with the unaided eye by the end of the month. It is worth keeping in mind and who knows, it might put on quite a show. Comet Panstarrs will be traveling in front of the two stars that are the leading edge of Leo the Lion’s mane or ‘backward sickle’. This part of Leo sets early in July so you will only have an opportunity to see the comet in the first week or so before the glare of the setting Sun overwhelms the comet. Use binoculars to try and sweep it up. Good luck and clear skies!

Article Photos

Father’s Day Sun-Jim Bonser (Touring the Skies) took this shot of the sun on Father’s day. He used a QHY5L-II ccd video camera on an 80mm scope with a 60mm Coronado h-alpha filter. Stacked the best of 100 frames each for the surface and prominances then processed and combined the images.